import sys # sys.setrecursionlimit(200005) # sys.set_int_max_str_digits(200005) int1 = lambda x: int(x)-1 pDB = lambda *x: print(*x, end="\n", file=sys.stderr) p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr) def II(): return int(sys.stdin.readline()) def LI(): return list(map(int, sys.stdin.readline().split())) def LLI(rows_number): return [LI() for _ in range(rows_number)] def LI1(): return list(map(int1, sys.stdin.readline().split())) def LLI1(rows_number): return [LI1() for _ in range(rows_number)] def SI(): return sys.stdin.readline().rstrip() dij = [(0, 1), (-1, 0), (0, -1), (1, 0)] # dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)] inf = (1 << 63)-1 # md = 10**9+7 md = 998244353 def nPr(com_n, com_r): if com_r < 0: return 0 if com_n < com_r: return 0 return fac[com_n]*ifac[com_n-com_r]%md def nCr(com_n, com_r): if com_r < 0: return 0 if com_n < com_r: return 0 return fac[com_n]*ifac[com_r]%md*ifac[com_n-com_r]%md n_max = 200005 fac = [1] for i in range(1, n_max+1): fac.append(fac[-1]*i%md) ifac = [1]*(n_max+1) ifac[n_max] = pow(fac[n_max], md-2, md) for i in range(n_max-1, 1, -1): ifac[i] = ifac[i+1]*(i+1)%md n,k=LI() ans=0 for r in range(1,n): ans+=pow(r,k,md)*nCr(n-1,r)%md ans%=md print(ans)